Yes, it has not been so overbought since Oct 07, so it is not rocket science to say that it will decline eventually. The missing and more critical piece of information is *when*, and by that I don't mean when a particular index reaches a particular level.
At some point it has to be more than a slight pullback from extreme OB and then a bounce right back up to set a new high, like it has for 11 days now. It may take some kind of watershed, exogenous event to generate sufficient downside momentum to make it stick.